Puretec RI-HF19, Руководство пользователя

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6 Installation & Operation Manual Copyright © Puretec Pty Ltd 2022
Application
Ultraviolet disinfection provides a simple, inexpensive way of destroying bacteria, mold, virus,
algae and fungi without the use of heat or chemicals. Each Puretec RI-HF system is designed
to achieve a specific energy dose to properly destroy microorganisms.
The dosage which applies to ultraviolet disinfection is proportional to energy, time, and area.
The total UV energy is attributed to the amount of energy emitted from all sides of a UV
lamp and is expressed in watts. The exposure is expressed in seconds and represents the total
time it takes for the water to flow through the UV chamber. The final factor in determining
the dosage relates to the total area and is expressed in m2. To summarize, the total dosage
is expressed in W-sec/m2 (or in some cases μW-sec/cm2, micro watt second per centimeter
squared, or J/m2).
• UV Disinfection is affected by many factors and the following should be looked at prior
to the installation of the UV system.
• UV Transmission (transmittance) deals with the effectiveness in which the 254
nanometer wavelength of ultraviolet light is transmitted through the water. The higher
the transparency of the water, the more effective the UV system becomes. This optical
clarity is evaluated by performing a test which passes incident light through a 1 cm
depth of water and recording this against the same test using distilled water as a
reference. This is done using a spectrophotometer.
• The basic designs of the units have taken into account a typical transmission at the
desired wavelength. In practical terms this means that a system designed to disinfect
a flow of about 3 m3/hr at a typical transmissibility (98%), could actually have a lower
flow rate in liquids with a lower transmissibility. As a general guideline, the following are
some typical UV transmission rates:
Deionized or reverse osmosis water: 98 - 100%
Typical filtered fresh water (e.g. rainwater): 94 - 98%
Lakes, bores, or other private sources: 70 - 94%
• WARNING: DO NOT UNDERSIZE UNITS
• If exact transmission quality needs to be determined, have samples tested at a suitable
lab using a proper spectrophotometer calibrated at 254 nm.
• Suspended Solids will act against a UV system by effectively shielding microorganisms
from the ultraviolet light. Dirt, rust, turbidity, etc. all have the ability to block out the
UV light. It is absolutely necessary to properly control the level of suspended solids by
properly pre-filtering the liquid prior to disinfection (pre-filtration down to 5 micron is
considered the minimum).
• Total Dissolved Solids of around 500 ppm can significantly reduce the rated flow rate of
the unit by absorbing UV energy. Proper pretreatment of high TDS levels must be taken
into account.
Application